Electrical device for transmitting to a distance continuous or intermittent angular movements.



F. SPALAZZI. ELECTRICAL DEVICE FOR TRANSMITTING TO A DISTANCE CONTINUOUS0R INTERMITTENT ANGULAR MOVEMENTS.

AFILIOATION FILED SEPT. 17, 1910; 1,066,159. Patented July 1, 1913.

/// v v g V I Attorned F. SPALAZZI. SMITTING TO A DISTANCE CGNTINUOUS 0RINTERMTTTBNT ANGULAR MOVEMENTS APPLICATION FILED $32 2.17, 1910. I

Patented July 1, 1913.

ELECTRICAL DEVICE FOR TRAN 1,066,159. 1 {a 2 HEETHHEBTZ 22L 1522' q 1 l6w 0 2/?" [12 41/ F S lH-VENTDR RAN CEsC P LPUL'ZL UNITED s'ing s gauroriaioa.

FRANCESCOSPALAZZI, OF NAPLES, ITALY.-

ELECTRICAL DEVICE FOR TRANSMITTING TO A DISTANCE CONTINUOUS OB, INTER-MITTENT ANGULAR MOVEMENT$.

Specification of Letters Patent,

Patented July 1 1913.

Application filed September 17, 1910. Serial No. 582,525.

T 0 all whom it may concern Be it known that I, FPANUESCO SPALAZZI,lieutenant in the Royal Navy, a subject of the King of Italy, andresiding at Naples, in the Kingdom of Italy, have invented certain newand useful Improvements in Elcctrical Devices for Transmitting to aDistance Continuous or Intermittent Angular Movements, of which thefollowing is a specification, reference being had therein to theaccompanying drawing.

The present invention refers to an ,electrical device of the classdescribed in the specification of patent application Serial N. 435523,by means of which the angular movements of a turning piece aretransmitted to a shaft situated far away, which repeats exactly whetherit is the case of continuous or intermittent movements. This ett'cct isobtained by means of a motor comprising a fixed field, in which a fluxof constant direction is produced, and a movable field comprising aplurality of coils, in which by, changing the path of the currentthrough the windings, a change of the direction of the resulting flux isobtained. The variation of the path of the current through the windingsis produced by the movement of a special switch which is put into actionby the turning piece.

The device according to the present application refers particularly toimprove-- ments in the construction of the repeating motor, and in orderthat said improvements may be fully understood the original form of themotor will be illustrated again in the drawings and briefly explained inthe description.

The improved motor c'unprises an armature with a'closed coil winding,which may be either multipolar or bipolar and permits of obtaining anydesired value of the driving torque within a given range, of minimixingthe variations thereof, increasing the eflieiency by reducing the airgap and maintaining the reluctance approximately constant for all thepositionsat the same time allo 'ing a larger number of positions for agiven nui'nber of transu'iitting wires. Further provisions are madewhich allow the motor to work with a strong current while avoidingdamage due to excessive sparking in the commutator.

This device can be advantageously utilized in many cases. For instanceit can be i utilized for transmitting to a distance the i indications ofa mariners compass, for regulating the sighting gear of the guns, fortransmitting the data for the tire to the guns of a distant battery, foractuating the devices of range finders with two observing stations, forcontrolling the position of the rudder of a ship, et cetera.

In the annexed drawings, Figures 1 to 8 show diagrammatically the formof the device described in the specification above referred to, in whichthe fixed field is formed by two electro-magnets and the movable fieldby a drum armature with 3 coils at 120. The other figures showdiagrammati- Fig. 1 is a plan view of the arrangement of the circuits ofthe motor and of its connections with the switch. Figs. 2 and 3 arerespectively an end view and a side elevation of the motor. Figs. 4 and5 are respectively an end view and a side elevation of the switch.- Fig.6 shows the diagrammatic disg position of a switch with liquidresistance. Fig. 7 shows a motor of the same type, but in which thearmature has a slotted cylindrical drum with smooth surface. Fig. 8shows a motor in which the disposition is reversed, viz. the rotor hastwo poles, in the windings of which current continuously flows, whilethe movable field is produced in the stator. Fig. 9 is another form ofarmature for the motor shown in Fig. '7. Figsl 10 and 11 show thedeveloped surface of two forms of the transmitting switch.

The fixed field of the motor shown in Figs. 1 to (S is formed by two,poles -l1"-, which can have a series-or a shunt excitation. Between saidpoles is placed a drum armature with 3 coils 2 222at 120 from each otherand each one of these 3 coils by means of a wire -fV-;-3 is connectedwith a metallic ring -4& t, Fig. 3, mounted upon the shaft 5- of themotor. It will be understood that mesh connected winding without areturn wire can be adopted. .In' this motor particular shapes are givento the pole-shoes of the field magnets and the core of the armature. Asis clearly shown in the drawing, (Fig. 2), tli pole shoes of thearmature expand outside the coils assuming a mushroom shaped appearanceand form together a nearly continuous cylindrical surface interruptedonly by the slots necessary cally the modifications now introduced.

for placing the windings of the coils in position. .The pole-shoes ofthe magnets of the field are also shaped in such away as to leave acylindrical recess, the diameter of whichis a little larger than thediameter of thearmature drum so that the air-gap is very small, and whenone of the pole-shoes of the armature is leaving the field of action ofone of the poleshoes of the field magnets, the following pole-shoes ofthe armature has already entered the said field. In the motor shown inthe drawing the excitation of the field and the windings of the armatureare connected in series, therefore there is only one wire -6- whichleads the current to the magnets of the fixed field wherefrom it goes tothe connecting point of the windings of the 3 coils of the armature. Theswitch which produces the variation of the current circulating in the 3coils of the armature consists of an insulating cylinder 9 mounted on ashaft 7 which either directly, or by means of suitable transmissionmechanism, is connected with the turning piece, the angular movements ofwhich are to be transmitted, so that it either rotatesthrough the sameangle or through a proportionally larger or smaller angle according tothe circumstances of the case. Upon the insulating cylinder 9 are placed3 continuous metallic rings 8'88-, and a ring divided into threesegments 99--9 each one of which communicates electrically with one ofthe continuous rings. Against the interrupted ring rests a large brush10-, to which the current is fed by the wire 1l. The contact surfaceofsaid brush is-smallcr than a segment of the ring, but it can keep incontact with two adjacent segments, so that the brush passes from onesegment to the other after having for a certain interval allowed thepassage of the current through both segments. When the current to betransmitted is of considerable strength, then, in order to diminishsparking, two or more brushes can be used acting on a like number ofinterrupted rings, the corresponding segments of which communicate withthe same continin ous ring. Against the three continuous rings 88-8-,rest three brushes 12'-1212, from .which start the wires 3.3 3, endingat the brushes -181813--, of the collector of the motor. From the fourthcollar l. l of the collector of the motor starts the return wire 6-.

passes from one segment to the other; however, when the brush begins tocover the succeeding segment and before it has left It will be easilyunder-- stood that by turning the shaft -7 of the preceding one, so thatthe current is circulating in two adjacent coils, the armature is turnedthrough 60. When it is a case of making use of an armature with star ormesh connected winding without the 4th wire, a path for the return ofthe current is provided by means of a brush at 180 from that by which,it enters. Fig. 10 shows "developed the cylindrical surface of a switchof this form; the current enters the system by the two brushes 22'22--,which are connected together, and the return wire 6- extendsto a secondair of brushes 22-22- which are diametrically opposite the brushesconnected with the wire 11. The contact segments -23--23- 23-, are inthis case of the special shape shown, and the current reaches thewindings 2-22' of the armature through the wires 33 8-starting from therings -24t"-2d2d-.

For series wound motors of the class shown in Fig. 1 switches having thearrangement shown in Fig. 11 may also be conveniently used.Thisarrangement ofi'ers the advantage of suppressing sparks and ofbraking the armature in each successive position. Fig. 11 shows thedeveloped cylindrical surface of the switch and clearly illustrates howthe segments --2'5-25-- 25-- are connected with the rings -26. 26'26-.The current reaches the switch through the double brush 25--, and 2727--are the shunting brushes.

The action of the rotary switch in combination with thearmature havingthree coils at 120 movable in a fixed field between a pair of oppositepoles is as follows: During the rotation of the switch current is sentalternatively through two wires to the three coils so that either in oneor two of same the current circulates in the same manner, while in theremaining coils or coil the current either flows in opposite directionor is altogether cut off from same. It ensues that for a given positionof the brush 10 relative to the segmental ring of the switch thearmature will remain fixed in a certain position until another step ismade by the switch, because contact is maintained at the collector ringand therefore the current still flows in the same manner in the coils.of the armature. At the instant however in which the brush -*10 eitherbegins to touch two adjacent segments or passes completely on one ofsame the armature rotates through a further 60. Therefore during therotation of the armature with three coils there are six stoppingpositions at 60 from each other. i

When it is desired to obtain a really continuous movement, it will beconvenient to make use of a liquid resistance switch arranged as shownin Fig. 6, and in this case in order to avoid the electrolysis of the vliquid, either alternating or inverted current should be preferred. Thisliquid resistance switch consists of a circular channel l6 havinginsulating walls and filled with a liquid of low conductivity. Into theliquid contained in this channel dips a metallic pin, which is carriedby an arm -17 mounted upon a shaft 18 passing through the center of thecircular channel 16. The shaft -18 is in the same way as the shaft -7 ofthe switch described hereinbefore, either directly or iiidirectlyconnected with the rotating piece, of whichit repeats, either enlargedor reduced, the angular movements. In one of the walls of the circularchannels --1 3, for instance, on the outer one, are inserted metallicplates tlie 1st,'the 4th, the 7th... of which are in communication withthe wire -3, the 2nd, the 5th, the 8th...

with the wire 3-, and the 3d, the (3th, the 9th with the wire 3"- thatis with the three wires which go to the collector of the motor. It willbe understood that when the pin carried by the arm 17 is in front of thesegment l9'-, the whole current coming from the wire -11- passes intothe wire 3'-, and during the motion of the arm a portion of the currentbegins to pass through the segment 19 until, when the pin carried bysame has arrived in front of the segment 19"-, the whole current passesthrough the wire -3" and so on. In this way the variation of thestrength of the current in two successive windings of the armature is acontinuous one and thus also the continuous rotation of the armature isobtained. In the walls of the channel can be fixed any number of groupsof plates, but it will be understood that when the rotating piece, theangular movements of which are to be repeated is the shaft -18-, thenfor the purpose of rendering sensible even small deviations it becomesnecessary to diminish the interval between successive plates, and toincrease accordingly the resistance of the liquid in which dips thepin,.if the same accuracy is to be obtained. It will also be apparentthat a switch of this class will be particularly useful in all cases inwhich the power acting on the shaft 18 and causing the rotation of sameis very weak and not sufficient for overcoming even a very smallmechanical resistance, as for instance in the case of the transmissionat distance of the indication of a mariners compass. In this case whenthe contact plates are inserted at .short intervals the motor described,acts as an amplifier of the movement.

Although in the drawing is shown a motor the armature of which has 3coils it will be understood that a greater number of coils, five forinstance, can be adopted, the number of the brushes being increasedaccordingly.

Thus any kind of closed coil armature winding wound on a slotted drumwith smooth cylindri -al surface as shown in Fig. 7, can serve for thepurpose, provided that the usual commutator be replaced by a ringcollector (similar to the collector shown, Fig. 3 each-ring beingconnected with one of the sections of the armature winding. By adoptingthis disposition the return path of the current is always by way of abrush resting against the segmental ring of the switch, and displaced by180? relative to that through which the current enters. Fig.

7 illustrates a motor of this class with two field poles ---2828, aclosed coil armature 29 having a smooth external surface and threesections -3030"-3O"--, communicating with the three rings of thecollector. The return path of the current is'by way of the wires -31-3l-3l*, all ending at a ring connection -?)2 from which starts the wire33- leading the current to the series wound field windings. The returnof the current takes place through the wire ---34. Another armature ofthis kindv with closed coil winding but without return wire isillustrated in Fig. 9. The advantages of this kind of armature areapparent: The airgap is reduced very small, the wire is better utilized,greater power is obtained and moreover the torque and the magneticreluctance are practically constant for all positions of the armature.This feature is of great importance, because in those motors where thereluctance of the magneticcircuit varies considerably for the variouspositions of the armature, the torque, beside overcoming the resistanceof the driven shaft. has to overcome also the resistance which thearmature, under the action of the field magnets, opposes to displacementwhen it occupies one of those positions for which the reluctance of themagnetic circuit is a minimum. Further a motor of the type shown inFigs. 7, 8 and 9 has the advantage that the angle betweentii'osiiccessive resting positions of the armature can be kept as smallas desired. Further it is clear that a synchronous movement can beobtained by reversing the position of the parts, viz., by forming thearmature with a coil wound on a conveniently shaped core and providing amultipolifr field either with several coils or with a closed coilwinding wherein the current is circulated, and in this case thecollector is no longer necessary and it will suflicc to connect directlythe windings of each coil or each section of the closed coil windingwith the brushes on the rings of the switch. Fig.

8 shows a motor of this kind with an arma-.

ture 35 formed by a coil the core of which has two mushroom shaped poleshoes, and closed coil field winding 29 to which the current eiitersdirectly fromthe rings of the switch through the threewires -36- 36-36.while .return takes place through the wires 37-3737, which end at thering connection -38 from which starts the return line -39-. It will beseen that irrespective of the particular arrangement of the parts thepresent inven tion substantially includes a switch conncot ed to aturning piece which during the rotation of the latter sends successivelythe current through a series of wires each one of which ends-at one ofthe rings of a ring collector, and a motor connected to the repeatingdevice and consisting of a fixed and a movable field formed either by acertain number of coils or by a closed coil winding, the winding of eachcoil, or each section of the armature winding being connected with aring of the collector which must therefore possess as many rings asthere are coils or sections of the winding so that on the turning of theswitch, the armature of the motor turns synchronously through anglescorresponding to the rotation of the field. In other words the switch incombination with the motor of the kind described provides for theproduction of a rotating field capable of rotating the armature andgenerated by means of continuous current, in such a manner that thepositions of rest of the armature can be made to differ by angles assmall as v desired.

In all the repeating motors used in connection with devices of thiskind, the constant field may include a plurality of pairs of poles, andarmatures with multipolar windings, that is the sections of which formeach as many poles as there are pairs of poles in the constant field, sothat the switch will perform two three, or more revolifitions for eachcomplete revolution of the. motor. Further in order to secure a constantmag netic reluctance it will be convenient to incline either the surfaceof the armature, or

the magnetic cores of the excitation. Lastly the etliciency of a motorof this class can be notably increased by forming the stationaryexcitation according to Fig. 8 by means of perforated metal sheets withholes near the sively sends current in a plurality of line wires endingin the repeating motor, the combination in said motor of a plurality ofcoils wound. so as to form a constant field, a closed coil winding insaid motor, co1nprising as many sections asthere are .line wires, eachsection forming as many poles of a variable field, the shoes of saidclosed coil windin forming a complete cylindrical surface whichcorresponds to the cylindrical surface limiting the pole shoes of thefirst constant'field, a shaft carrying one of said windings, the otherbeing stationary; continuous rings and electrical connections on saidshaft feeding in the same manner the winding carried by the shaftirrespective of the position of the latter, each section of the closedcoil winding bemg in communication with one of the line wires, and thecoils of the constant field being in communication with the return line,so that all of them are energized in the same manner and produce amagnetization, the direction of which in respect of the coils isconstant, the sections of the closed coil winding being energized in amanner cyclically variable with the roing variable field, thus compellinthe movable'winding mounted on the shaft to rotate by the same angle asthe variable field In testimony whereof I have atlixed my signature inpresence of two witnesses.

FRANGESCQ SPALAZZI.

Witnesses:

Ln'rrnmo LABOCCETTA, ANTONIO LABOCCETTA.

tation of the switch and producing a rotat-

